Component mounting device and position recognition method

ABSTRACT

A component mounting device capable of selectively performing a tolerance check mode that recognizes a position of a lead after determining whether the size of a lead region is within a tolerance range, and a non-tolerance check mode that recognizes a position of the lead without performing determination of whether the size of the lead region is within the tolerance range. Therefore, even in cases in which it is difficult to set a tolerance range due to the tip of the lead being covered with a viscous fluid such as solder or plating, the position of the lead is appropriately recognized.

TECHNICAL FIELD

The present invention relates to a component mounting device and aposition recognition method.

BACKGROUND ART

Conventionally, there is a component mounting device for mounting acomponent with leads onto a board by inserting the leads into insertionholes of the board. For example, a component mounting device of patentliterature 1 shines light from the sides of the leads, images thecomponent from below, detects regions with the same shape as a crosssection of the leads from the captured image as the positions of theleads, then corrects the mounting position of the component on the boardbased on the positions of the detected leads. Further disclosed issubsequently applying solder to the leads of the mounted component.

CITATION LIST Patent Literature

Patent literature 1: JP-A-2002-280799

SUMMARY OF INVENTION Technical Problem

However, there are cases in which components are mounted by beinginserted into insertion holes of a board after solder has been appliedto the leads of the component. In this case, because leads with solderapplied are imaged from below, a region larger than the cross section ofthe lead may appear in the image. Therefore, with a component mountingdevice such as the one above that detects a region with the same shapeas a cross section of a lead as the position of the lead, the positionof the lead may not be detected correctly.

An object of the present invention is to more appropriately detect aposition of a lead of a component.

Solution to Problem

The present invention uses the following means to achieve the aboveobject.

A component mounting device of the present invention is for mounting acomponent with a lead onto a board by inserting the lead into aninsertion hole of the board, the component mounting device including:

an imaging device configured to image the component in a state beingheld; and

a processing section configured to perform recognition processing forrecognizing a position of the lead by processing a captured imagecaptured by the imaging device, the processing section being furtherconfigured to selectively perform

first recognition processing of extracting a lead region from thecaptured image, performing region determination of determining whether asize of the lead region is within a specified tolerance range, and in acase in which the size of the lead region is determined to be within thespecified tolerance range, recognizing the position of the lead based onthe lead region, and

second recognition processing of extracting the lead region from thecaptured image and recognizing the position of the lead based on thelead region without performing the region determination.

With a component mounting device of the present invention, it ispossible to selectively perform first recognition processing ofextracting a lead region from the captured image, performing regiondetermination of determining whether a size of the lead region is withina specified tolerance range, and in a case in which the size of the leadregion is determined to be within the specified tolerance range,recognizing the position of the lead based on the lead region, andsecond recognition processing of extracting the lead region from thecaptured image and recognizing the position of the lead based on thelead region without performing the region determination. By performingthe first recognition processing, it is possible to appropriatelyrecognize the position of the lead from the lead region that is withinthe specified tolerance range. Further, by performing the secondrecognition processing, because the position of the lead can berecognized without setting a specified tolerance range, it is possibleto appropriately recognize the position of the lead even in a case inwhich it is difficult to set a tolerance range due to the tip of thelead being covered with a viscous fluid such as solder or plating.

A component mounting device of the present invention may further includea memory section configured to memorize position information of the leadfor the component, wherein the processing section extracts from thecaptured image a region corresponding to a position based on theposition information of the lead as the lead region. Accordingly,incorrect detection of the position of the lead is prevented in thesecond recognition processing in which region determination is notperformed.

With a component mounting device of the present invention the processingsection, during the second recognition processing, may recognize theposition of the lead based on the lead region after checking that thesize of the lead region does not correspond to a specified exceptionrange that is larger than the tolerance range. Accordingly, in a case inwhich the lead region corresponds to the specified exception range dueto, for example, being extremely large with respect to the leaddiameter, it is possible to not perform recognition of the lead positionin the second recognition processing.

A component mounting device of the present invention may further includea receiving section configured to receive a selection by an operator ofeither the first recognition processing or the second recognitionprocessing, wherein the processing section performs the firstrecognition processing or the second recognition processing based on theselection by the operator. Accordingly, the position of the lead can bedetected appropriately with greater freedom for an operator to selectprocessing.

A position recognition method of the present invention is forrecognizing a position of a lead of a component, the positionrecognition method including: (a) imaging the component in a state beingheld; and (b) performing recognition processing for recognizing aposition of the lead by processing a captured image captured in (a),wherein in (b) a step (b1) of extracting a lead region from the capturedimage, performing region determination of determining whether a size ofthe lead region is within a specified tolerance range, and in a case inwhich the size of the lead region is determined to be within thespecified tolerance range, recognizing the position of the lead based onthe lead region, and a step (b2) of extracting the lead region from thecaptured image and recognizing the position of the lead based on thelead region without performing the region determination, are selectivelyperformed.

With a position recognition method of the present invention, it ispossible to selectively perform a step (b1) performing regiondetermination of determining whether a size of the lead region extractedfrom a captured image is within a specified tolerance range, and in acase in which the size of the lead region is determined to be within thespecified tolerance range, recognizing the position of the lead based onthe lead region, and a step (b2) recognizing the position of the leadbased on the lead region extracted from the captured image withoutperforming the region determination. Using step (b1) it is possible toappropriately recognize the position of the lead from the lead regionthat is within the specified tolerance range. Also, using step (b2),because the position of the lead can be recognized without setting aspecified tolerance range, it is possible to appropriately recognize theposition of the lead even in a case in which it is difficult to set atolerance range due to the tip of the lead being covered with a viscousfluid such as solder or plating.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1

FIG. 1 schematically illustrates the configuration of component mountingdevice 10.

FIG. 2

FIG. 2 is a block diagram showing the configuration of control relateditems of component mounting device 10.

FIG. 3

FIG. 3 schematically illustrates the configuration of component camera30.

FIG. 4

FIG. 4 is a flowchart showing an example of component mountingprocessing.

FIG. 5

FIG. 5 is a flowchart showing an example of lead position recognitionprocessing.

FIG. 6

FIG. 6 illustrates an example of a tolerance range.

FIG. 7

FIG. 7 illustrates an example of a recognition state of a lead positionusing the tolerance range.

FIG. 8

FIG. 8 illustrates an example of a processing exception error.

FIG. 9

FIG. 9 illustrates an example of recognizing a lead position withoutusing a tolerance range.

DESCRIPTION OF EMBODIMENTS

FIG. 1 schematically illustrates a configuration of component mountingdevice 10 and FIG. 2 is a block diagram showing the configuration ofcontrol related items of component mounting device 10. Note that, inFIG. 1, the left-right direction is the X-axis direction, the front-reardirection is the Y-axis direction, and the up-down direction is theZ-axis direction.

As shown in FIG. 1, component mounting device 10 is provided withcomponent supply device 12 that supplies components P, board conveyancedevice 16 that conveys board B that is flat, board holding device 18that holds board B that was conveyed, head 20 attached to which iscomponent chuck device 22 used to grip component P, and moving mechanism24 for moving head 20 in XY directions. Also, component mounting device10 is provided with mark camera 26 that images marks provided on boardB, component camera 30 that images components P held by component chuckdevice 22, operation panel 28 (refer to FIG. 2) provided with selectionbutton 29 and the like for receiving various operation instructions froman operator, and control device 50 that performs overall control ofcomponent mounting device 10. Component chuck device 22 grips componentP using chuck claws that can open and close, and is removably attachedto head 20. As well as component chuck device 22, a component suctiondevice that picks up component P using a nozzle may be attached to head20.

Component supply device 12 is provided with tape feeder 13 or the likefor supplying components P by feeding tape holding leaded components P(such as radial components as shown in FIG. 1 or axial components thatare not shown). Tape feeder 13 supplies components P (refer to FIG.1[a]) for which the tips of the leads L are not applied with viscousfluid such as solder 5 or plating and components P (refer to FIG. 1[b])for which the tips of the leads L are applied with viscous fluid such assolder 5 or plating. The application amount of solder 5 or the like andthe shape after application may vary between each component P, and mayvary between each lead L of the same component P. When component P ismounted onto board B, leads L are inserted into insertion holes formedin board B.

Head 20 is provided with a raising and lowering mechanism and a rotationmechanism, which are not shown, to rotate around an axis (spin) andraise and lower in the Z-axis direction component chuck device 22 or acomponent suction device attached to head 20. An air path connected to anegative pressure source such as an air pump, which is not shown, isalso provided in head 20. Head 20 grips component P with component chuckdevice 22 or picks up component P with the component suction device bynegative pressure being supplied from the negative pressure source viathe air path.

Component camera 30 images component P gripped by component chuck device22 from below when the component P passes above component camera 30 andoutputs the captured image to control device 50. FIG. 3 schematicallyillustrates the configuration of component camera 30. As shown in FIG.3, component camera 30 is provided with imaging element 32 with arectangular imaging region formed from multiple light receiving elementsarranged in a two-dimensional grid, such as a CCD, lens 34 providedabove imaging element 32, and lighting device 36 that shines light fromthe sides of the leads when component P is being imaged.

Control device 50 is configured from items such as a CPU, ROM, RAM, andan HDD, and performs overall control of the mounting device. As shown inFIG. 2, control device 50 outputs drive signals to each of componentsupply device 12, board conveyance device 16, and board holding device18, outputs drive signals to head 20 (component chuck device 22),outputs drive signals to moving mechanism 24, and outputs drive signalsto mark camera 26 and component camera 30. Also, control device 50receives operation signals from operation panel 28 and receives imagescaptured by mark camera 26 and component camera 30. Control device 50memorizes an image processing program and various types of informationon memory section 52, which is ROM or an HDD or the like. Memory section52 memorizes component information related to component P with leads.Component information includes component type indicating the type ofcomponent P, a quantity of leads L that component P has, a centerposition of each lead L, and an outer diameter of leads L. The centerposition of lead L is, as position coordinates at which the center ofleads L exist in the captured image of component P being held in a statenot tilted at an angle or deviated, represented by XY coordinates takingthe center position of the captured image (the center of component Pcaptured by component camera 30) as a reference. For example, from thetwo leads on component type “PA”, the coordinates (Xla, YLa) are definedas the center of the left side lead (L).

Below, an operation of the component mounting apparatus 10 configured asdescribed above will be described. FIG. 4 is a flowchart showing anexample of component mounting processing. This processing is performedby control device 50.

When component mounting processing is performed, control device 50,first, grips component P supplied from component supply device 12 withcomponent chuck device 22 (S100). Control device 50 controls componentsupply device 12 such that component P is fed to a component supplyposition, and controls moving mechanism 24 and head 20 such that head 20is positioned above the component supply position and the component P isgripped by component chuck device 22. Continuing, control device 50controls moving mechanism 24 such that the component P gripped bycomponent chuck device 22 is moved above board B via a route overcomponent camera 30 (S110), and controls component camera 30 to imagecomponent P when component P is above component camera 30 (S120). Next,control device 50 performs lead position recognition processing torecognize the position (center position) of leads L by processing theimage captured in S120 (S130). Details of this lead position recognitionprocessing are described later.

Then, control device 50 corrects the mounting position of component Pbased on the recognized positions of leads L (S140), mounts thecomponent P at the corrected mounting position on board B (S150), thenends component mounting processing. Here, component P gripped bycomponent chuck device 22 may be tilted or deviated from a normal state.Therefore, control device 50, to correctly insert leads L into insertionholes of board B, mounts component P on board B in S150 after correctingthe mounting position in the XY direction and the mounting direction inan axial direction based on the positions of the leads L in S140. Also,control device 50, in S150, controls moving mechanism 24 and head 20such that the tips of leads L of component P held by component chuckdevice 22 are directly above the insertion holes of board B. Further,control device 50 controls head 20 such that component chuck device 22is lowered until leads L are inserted into the insertion holes, thenturns off the supply of negative pressure from the negative pressuresource such that the grip of component P by component chuck device 22 isreleased and the component P is mounted on the board.

Next, lead position recognition processing of S130 is described. FIG. 5is a flowchart showing an example of lead position recognitionprocessing. Note that, images for which the gradient value of each pixelis 8-bit grayscale are acquired as captured images.

In lead position recognition processing, control device 50, first,determines whether the component type that is the current target forprocessing has changed from the previous target for processing (S200).Control device 50, upon determining that the component type has changed,reads the lead diameter and the coordinates of the center position ofeach lead L of the corresponding component type from the componentinformation memorized on memory section 52 (S210). Note that, controldevice 50, upon determining that the component type has not changed inS200, may skip the processing of S210.

Next, control device 50 acquires the gradient value of each pixel of thecaptured image (S220), then performs binarization processing ofbinarizing each pixel using a specified binarization threshold (S230).Binarization may be performed using a well-known method such as P-tile,mode, or discriminant analysis appropriate for detecting leads L (tipsurfaces) within the image. When binarization is performed, controldevice 50 determines whether the execution mode of the current leadposition recognition processing is tolerance check mode (S240). In thepresent embodiment, control device 50 is able to perform two executionmodes for lead position recognition processing: tolerance check mode(first recognition processing) and non-tolerance check mode (secondrecognition processing). Also, an operator is able to select tolerancecheck mode and non-tolerance check mode using selection button 29 ofoperation panel 28, with control device 50 performing the mode selectedby the operator.

Here, FIG. 6 illustrates an example of a tolerance range. The tolerancerange is defined based on the diameter φL of lead L (FIG. 6[a]), thediameter of the insertion hole, or the like. In the present embodiment,the tolerance range is defined as the range of diameter φ (L+t) that istolerance t added to diameter φL of lead L (FIG. 6[b]). Tolerance t, forexample, is set such that the area of diameter φ (L+t) is a multiple (2to 3 times, for example) of the area of diameter φL. Note that, thetolerance range may be set such that a tolerance t of a few millimetersis added to diameter φL. The tolerance range (tolerance t) may be set byan operator using operation panel 28 or the like.

Control device 50, upon determining in S240 that the mode is tolerancecheck mode, performs extraction processing of lead regions correspondingto the center position of leads L from the binarized image (S250), thencalculates the area of the lead region (S260). Continuing, controldevice 50 determines whether the calculated lead region area is withinthe tolerance range (S270).

FIG. 7 illustrates an example of a recognition state of a lead positionusing the tolerance range. As shown, control device 50 extracts as thelead region a collected region of pixels for which the binarized pixelvalue is a value of a color (white) indicating a lead L, the regionincluding each of the center positions (XLa, YLa) and (XRa, YRa) ofleads L from S250. Note that, control device 50 may extract a collectionregion of pixels for which the binarized value is a value of a color(white) indicating a lead L, and then extract as a lead region a regionfrom the extracted region such that the distance between the center ofthe regions corresponds to the distance between the center of the leadsL. In this case, memory section 52, instead of the center positions ofleads L, memorizes relative position information such as the distancebetween the centers of the leads L. Control device 50 determines thatthe area of the lead region is within the tolerance range in a caseshown in FIG. 7(a), and determines that the area of the lead region onthe left is outside the tolerance range in a case shown in FIG. 7(b).Note that, control device 50 determines that the area of the lead regionis outside the tolerance range when the lead region is large due toforeign matter such as dirt or dust is adhered to lead L, or when aviscous fluid such as solder or plating has been applied to the tip ofthe lead L. Control section 50, upon determining in S270 that the areaof the lead region is within the tolerance range, recognizes the centerposition of the extracted lead region as the center position of lead Lof component P being gripped by component chuck device 22 (S280), thenends processing. In the example of FIG. 7(a), control device 50recognizes center position CL of the lead region on the left and centerposition CR of the lead region on the right as the respective centerpositions of the leads L. On the other hand, control device 50, upondetermining in S270 that the area of the lead region is outside thetolerance range, reports an errors (S290), then ends processing. Inother words, control device 50 determines a defect and issues an errornotice when the area of the lead region exceeds the tolerance range thatrepresents the maximum area that is allowable.

Also, control device 50, upon determining in S240 that the mode is thenon-tolerance check mode rather than the tolerance check mode, similarto S250, performs extraction processing of extracting the lead regionfrom the binarized image (S300). Then, control device 50 determineswhether a specified processing exception error has occurred (S310).

FIG. 8 illustrates an example of a processing exception error. As shown,a processing exception error corresponds to a case in which the pixelvalues for the entire binarized image are values of the color (white)indicating a lead L such that the lead region cannot be extracted (FIG.8[a]), or a case in which the extracted region (the white region in theimage) is extremely large (FIG. 8[b]). Note that, an extremely largelead region may arise, for example, in a case in which the area of thediameter φL of the lead region is many times larger (for example, 25times or 30 times larger) when using a value such that the area ofdiameter φ(L+t) when using tolerance t is several times the area ofdiameter φL.

Control device 50, upon determining that a processing exception errorhas occurred in S310, reports the error (S320), then ends processing.That is, control device 50, in a case in which the processing target isan exception such as when the area of the lead region is extremelylarge, determines a defect and reports an error without recognizing theposition of lead L. On the other hand, control device 50, upondetermining in S310 that there is no processing exception error,recognizes the center position of the lead region extracted in S300 asthe center position of lead L of component P being gripped by componentchuck device 22 (S330), then ends processing. In this manner, controldevice 50, when performing non-tolerance check mode, recognizes thecenter position of the extracted lead center as the center position oflead L as is without determining whether the extracted lead region iswithin the tolerance range.

FIG. 9 illustrates an example of recognizing a lead position withoutusing a tolerance range. As shown, the center position of the leadregion is recognized as the respective center positions CL and Cr of theleads as is without comparing the lead regions to a tolerance range.Note that, as shown in FIG. 9, a region other than a lead region appearsin the image (a region shown by hatching), but this region does notinclude the center position of a lead L, and does not correspond to acenter position of a lead L. Therefore, control device 50, in processingof S300, does not consider this region as a candidate region whenrecognizing the lead position so does not extract it. Thus, controldevice 50 is able to prevent misrecognition of the center position oflead L due to treating this region as a lead region.

Correspondences between constituent elements of the present embodimentand constituent elements of the invention will be clarified here.Component mounting device 10 of the present embodiment corresponds to acomponent mounting device of the present invention, component camera 30corresponds to an imaging device, and control device 50 corresponds to aprocessing section. Also, memory section 52 corresponds to a memorysection, and operation panel 28 (selection button 29) corresponds to areceiving section. Note that, from descriptions of operation ofcomponent mounting device 10 of the present embodiment, an example of aposition recognition method of the present invention is also clear.

Component mounting device 10 as described above is able to selectivelyperform a tolerance check mode that recognizes a position of a lead Lafter determining whether the size of a lead region is within atolerance range (region determination), and a non-tolerance check modethat recognizes a position of a lead L without performing determinationof whether the size of the lead region is within the tolerance range.Therefore, even in cases in which it is difficult to set a tolerancerange due to the tip of the lead L being covered with a viscous fluidsuch as solder S or plating, the position of lead L is appropriatelyrecognized.

Also, because component mounting device 10 extracts a collection regioncorresponding to a center position of leads L memorized on memorysection 52, in the non-tolerance check mode, it is possible to preventmisdetection of the position of lead L.

Further, because component mounting device 10, in the non-tolerancecheck mode, checks whether a processing exception error occurredcorresponding to a case in which the size of the lead region was in aspecified exception range, it is possible to prevent misdetection of theposition of lead L.

Also, because component mounting device 10 receives the selection of thetolerance check mode or the non-tolerance check mode from an operator,the position of lead L can be detected appropriately with greaterfreedom for an operator to select processing. For example, when mountinga component P for which a relatively high mounting accuracy is required,an operator may select the tolerance check mode, but when mounting acomponent P with solder S applied, the operator may select thenon-tolerance check mode.

Meanwhile, it goes without saying that the invention is not limited tothe above-mentioned embodiment and various embodiments may be appliedwithin the technical scope of the invention.

For example, in an embodiment above, a collected region of pixels of acolor indicating lead L and corresponding to a center position of lead Lmemorized on memory section 52 is extracted as the lead region, but theconfiguration is not limited to this, a collected region of pixelssimply indicating lead L may be extracted as the lead region.

In an embodiment above, a check for a processing exception error isperformed in the non-tolerance check mode, but the configuration is notlimited to this, and it is not necessary to perform a check for aprocessing exception error. In this case, in the non-tolerance checkmode, control device 50 omits processing of S310 and S320, and mayrecognize the center of the lead region extracted in S300 as the leadcenter in S330.

In an embodiment above, the selection of the tolerance check mode andthe non-tolerance check mode is received from an operator, but either ofthe modes may be performed selectively without receiving a selectionfrom an operator. For example, control device 50, in a case in which itis possible to receive information about whether a viscous fluid such assolder 5 is on lead L of component P, may select which mode to use basedon the acquired information. That is, control device 50, in a case ofacquiring information indicating that solder 5 or the like is not onlead L, may recognize the position of lead L with the tolerance checkmode, and, in a case of acquiring information indicating that solder 5or the like is on lead L, may recognize the position of lead L with thenon-tolerance check mode.

In an embodiment above, it is possible to selectively perform thetolerance check mode and the non-tolerance check mode, but theconfiguration is not limited to this, and it is possible to performedonly the non-tolerance check mode. That is, control device 50 mayperform recognition processing to recognize the position of the lead Lbased on the lead region without performing a determination of whetherthe lead region extracted from the captured image is within thespecified tolerance range.

INDUSTRIAL APPLICABILITY

The present invention may be applied to mounting work of mountingcomponents on a board.

REFERENCE SIGNS LIST

10: component mounting device;

12: component supply device;

13: tape feeder;

16: board conveyance device;

18: board holding device;

20: head;

22: component chuck device;

24: moving mechanism;

26: mark camera;

28: operation panel;

29: selection button;

30: component camera;

32: imaging element;

34: lens;

36: lighting device;

50: control device;

52: memory section;

B: board;

L: lead;

P: component;

S: solder

1.-5. (canceled)
 6. A component mounting device for mounting a componentwith a lead onto a board by inserting the lead into an insertion hole ofthe board, the component mounting device comprising: an imaging deviceconfigured to image the component in a state being held; and aprocessing section configured to perform recognition processing forrecognizing a position of the lead by processing a captured imagecaptured by the imaging device, the processing section being furtherconfigured to selectively perform first recognition processing ofextracting a lead region from the captured image, performing regiondetermination of determining whether a size of the lead region is withina specified tolerance range, and in a case in which the size of the leadregion is determined to be within the specified tolerance range,recognizing the position of the lead based on the lead region, andsecond recognition processing of extracting the lead region from thecaptured image and recognizing the position of the lead based on thelead region without performing the region determination.
 7. Thecomponent mounting device according to claim 6, further comprising amemory section configured to memorize position information of the leadfor the component, wherein the processing section extracts from thecaptured image a region corresponding to a position based on theposition information of the lead as the lead region.
 8. The componentmounting device according to claim 6, wherein the processing section,during the second recognition processing, recognizes the position of thelead based on the lead region after checking that the size of the leadregion does not correspond to a specified exception range that is largerthan the tolerance range.
 9. The component mounting device according toclaim 6, further comprising a receiving section configured to receive aselection by an operator of either the first recognition processing orthe second recognition processing, wherein the processing sectionperforms the first recognition processing or the second recognitionprocessing based on the selection by the operator.
 10. A positionrecognition method for recognizing a position of a lead of a component,the position recognition method comprising: (a) imaging the component ina state being held; and (b) performing recognition processing forrecognizing a position of the lead by processing a captured imagecaptured in (a), wherein in (b) a step (b1) of extracting a lead regionfrom the captured image, performing region determination of determiningwhether a size of the lead region is within a specified tolerance range,and in a case in which the size of the lead region is determined to bewithin the specified tolerance range, recognizing the position of thelead based on the lead region, and a step (b2) of extracting the leadregion from the captured image and recognizing the position of the leadbased on the lead region without performing the region determination,are selectively performed.